1995 Plymouth Voyager

LESAB98

1995 PLYMOUTH VOYAGER

The problem that this vehicle had was that after driving arounnd for a few hours, it refused to start.
this van has a 3.3 or3.8 v-6, and has only done this once, then was allowed to sit for a while, and then started right up.
What may have caused this? It now seems to be fine, and starts up as normal. I want to check it out and prevent another occurance